Sandblast nozzle



Dec. 24, 1 94s. BUGLgY 2,413,167

SANDBLAST NOZZLE Filed July 10,, 1945 f 2 ll &

Patented Dec. 24, 1946 UNITED STATES This invention has for an object toproduce a nozzle for sand blasting wherein the wear, due to erosion ofthe sand on the nozzle, will be less rapid than heretofore.

This is accomplished, in accordance with this invention, by treatingwith or applying to the bore of the nozzle, a coating of hard materialhighly resistant to the abrasive action of the sand, such as commercialdiamond dust. Such dust may be charged into a relatively soft metalretaining medium and then the medium may be hardened. A materialparticularly suitable for this purpose is known to the trade asberyllium copper. A representative formula for such material comprises2% beryllium, 0.25% cobalt, and the remainder copper. When such materialis quenched, say, from 800 C. it is in its annealed soft state. The boreof such material which either forms a coating on the inner face of thenozzle, or is formed as a tubular insert which may be placed in positionwithin the nozzle, is charged on its inner surface with the diamond dustby methods well known in the art, and the material so charged is thensubjected to heat at from 250 C. to 350 C. for a sufficient length oftime, commonly about seven or eight hours, to reach its maximumhardness.

For a complete understanding of this invention, reference may be had tothe accompanying drawing in which Figure 1 is an isometric view of aberyllium copper sleeve insert charged on its inner face with thediamond dust.

Figure 2 is a view partly in side elevation and partly broken away andin section of a sand blast nozzle to which the insert of Figure 1 hasbeen applied.

Figure 3 is a cross sectional view or a nozzle having a diamond dustcharge in a coating of beryllium copper in its inner face.

Figure 4 i a view partly in side elevation and partly in section of thenozzle of Figure 3.

Referring to the drawing, at l in Figure 1 is shown a sleeve of materialadapted to have the commercial diamond dust which comprises fineparticles of the hard commercial diamond material charged into its innerface. This sleeve may well be of beryllium copper which can be annealedin soft condition in which it may be readily worked, and in whichcondition its central bore 2 may have charged into the surface thereofthe commercial diamond dust as at 3 forming an exceedingly hard innersurface coating. The sleeve may then be hardened, the beryllium copperhardening when its temperature is raised from 250 C. to 350 C. and thereheld for some hours, say seven or eight, at which time the berylliumcopper attains its maximum hardness. If the heating be continued beyondthe maximum point, the hardness tends to decrease to some extent.

PATENT OFFICE SANDBLAST NOZZLE James R. Bugley, Boston, Mass, assignorof onehalf to Raymond Hunter, Boston, Mass.

Application July 10, 1945, Serial No. 604,256

3 Claims. (CI. 5111) As shown, the sleeve l is provided with aperipheral groove 4 to receive the inner end of one or more set screws 5threaded through the outer wall of the nozzle (5, which is provided witha recess 1 adjacent to its outer end shaped to receive the insert sleevei and with its central bore 8 forming a continuation of the bore of thesleeve. Since the size of the nozzle at the exit end determines thepressure of the jet of the sand blast for any given pressure and volumeof air, the maintenance of this exit opening at the proper size is ofgreat importance, while the matter of increase of size of the jetopening back of the exit opening is of little consequence in determiningthe pressure of the blast as it issues from the nozzle. Hence in orderto economize, the more expensive beryllium copper and the commercialdiamond dust may be localized, as shown in Figure 2, adjacent to theexit end of the nozzle. However, if desired, the entire length of thebore of the nozzle may have its inner face impregnated with the diamonddust and when this is desired, it is preferable to coat the inner wallof the nozzle with beryllium copper since this furnishes a medium whichcan be made sufiiciently soft to be thoroughly impregnated with thediamond dust after which it may be made hard to hold the diamond dust inposition and to aid in resisting erosion of the nozzle by the sand. Forexample, the nozzle itself may comprise a tube ill of material such ascast iron suitably shaped to connect it to the source of supply of sandand compressed air, and provided with a central bore H, the surface ofwhich is charged with the commercial diamond dust, preferably in a layerof beryllium copper applied to the inner face of the cast iron tube byany suitable means such as electrodeposition, brazing of a liner tube,or otherwise, such means being well known in the art.

From the foregoing description of certain embodiments of this inventionit should be evident to those skilled in the art that various otherchanges and modifications might be made without departing from thespirit or scope of this invention.

I claim:

1. A nozzle element comprising a metal tube having its inner faceimpregnated with commercial diamond dust particles.

2. A nozzle element comprising a tube of hardened beryllium copperhaving its inner face impregnated with commercial diamond dustparticles.

3. A nozzle having an inner bore provided with an enlarged diameterrecess in its outer end, a sleeve of beryllium copper seated in saidrecess, said sleeve having its inner face impregnated with commercialdiamond dust particles, and means for securing said sleeve in saidrecess.

JAMES R. BUGLEY.

